Prior to setting forth the background of the related art, it may be helpful to set forth definitions of certain terms that will be used hereinafter.
The term “electrical signature” as used herein in this application, is defined as parameters of a signal received from an electrical appliance. The electrical signature may be characterized by continuous and/or discrete waveforms of current, power and/or voltage and are typical to appliances, working modes, connectivity types etc.
The term “outlet” as used herein in this application, is defined as a wall mounted and/or pluggable electrical plugs and sockets. An outlet may connect to AC (Alternating Current) or DC (Direct Current) power cable on one side (the “network” side, referring to the electrical grid or generator side), and may be connected to an AC or DC power cable (or cables) on the other side (refers to the appliances side). The cable(s) on the appliance side may connect to one or more appliances. The cable on the appliance side and the network side may or may not be connected to the outlet at a certain moment. AC outlets include both single phase outlets and three-phase outlets. The term “outlet” herein may refer to a single plug and socket or a strip of plugs and sockets. The term “outlet” also includes implementations and devices where such outlet is implemented as a subunit in an appliance.
Although AC power supply is characterized by a sinusoidal voltage, non-linear loads may draw non-sinusoidal current which is characterized by added harmonics to the original sinusoidal supply. Non-linear loads are exhibited e.g. by saturated magnetic such as transformers and rotating machines, fluorescence light, power electronic load such as switched mode power supply, rectifiers (e.g. DC motors, regulated PS, battery chargers) and inverters.
As electricity prices rise, the need for energy management systems and energy saving systems becomes crucial. Existing energy management systems are able to manage special appliances that employ special communications and remote control capabilities. Alternatively energy management systems manage appliances inefficiently, without having accurate information on the appliance status, the power it consumes and whether it is turned ON.
There is a need for reducing peak consumption from the electric network, as the peaks are those that demand most efforts to overcome by electric companies, and as a result cause most marginal damage to consumers relying on the electric network and to the environment. There is also an interest for reducing overall consumption from the electric network, to save money, reduce pollution and help the environment.
Existing solutions to the problem of reducing peak and non-peak demands require professional installation at customer premises, and reliable end-to-end management systems, which are difficult to achieve. Alternatively, customers are being asked to reduce consumption at peak and non-peak periods, but not always have the tools to control their consumption, nor do the suppliers have the tools to control the customers.
U.S. Patent Publication No. US20080164768, which is incorporated herein by reference in its entirety, discloses a power conservation apparatus having a power inlet for providing power to the power conservation apparatus and an external appliance, a power outlet operable to be connected to the appliance, a relay coupling the power inlet and the power outlet, a current sensor operable to measure a current flow from the power outlet to the appliance, a threshold detector operable to receive an input in accordance with the current flow and operable to determine if the appliance is in a state of non-use, and a timer having a set-point; wherein the timer is activated upon the appliance entering the state of non-use and wherein the relay is opened upon the timer reaching the set-point, so as to prevent the power conservation apparatus and the appliance from drawing power from the power inlet. When in the “off” state, the AC power consumed by the apparatus and coupled appliances is zero.
U.S. Pat. No. 6,934,862, which is incorporated herein by reference in its entirety, discloses a device that monitors an appliance that receives power from a source. The device includes a first coupler that couples the device to the power source. A second coupler couples the device to the appliance. A monitoring circuit is connected to the first coupler and the second coupler to monitor power supplied by the source to the appliance. A communications circuit also is provided. The monitoring circuit provides data based on the monitored power to the communications circuit for output to the first coupler. The communications circuit may include a receiver that receives a signal from the first coupler to control the monitoring circuit. The communications circuit also may include a transceiver that receives a signal from the first coupler to control the monitoring circuit and to transmit monitored power data. The monitoring circuit includes a memory that stores an electronic signature of the appliance and a processor that determines an operating state of the appliance based on the electronic signature
WIPO Publication No. WO07136213, which is incorporated herein by reference in its entirety, discloses a power outlet device comprising a relay socket main detachably inserted between a main power outlet and a plug of an electrical appliance. The relay socket main body includes a control circuit configured to internally and selectively supply and cut off a commercial AC power to the electrical appliance according to detection of current state corresponding to a power-on or power-off state of the electrical appliance and an external power-on request of the relay socket main body. The relay socket main body includes a control circuit configured to internally and selectively supply and cut off a commercial AC power to the electrical appliance according to detection of current state corresponding to a power-on or power-off state of the electrical appliance and an external power-on request of the relay socket main body. if a current value corresponding to non-operation is detected from the electrical appliance being operated, the control circuit confirm whether or not the non-operation is valid while monitoring the detected current value for a first time interval, and thereafter if the non-operation state is maintained after a stand-by while monitoring the detected current value for a second time interval, the control circuit internally cuts off the passage of the commercial AC power being supplied to the electrical appliance through the relay socket main body.
WIPO Publication No. WO05076416, which is incorporated herein by reference in its entirety, discloses a multifunctional multi-tap of intercepting a stand-by electric power and a control method employing the same which prevent big fire generated by leakage current by performing an interlocking control and a single-acting control in accordance with subordination of respective appliances using a illumination sensor or a body-detecting sensor.
U.S. Pat. No. 4,644,320, which is incorporated herein by reference in its entirety, discloses a home energy monitoring and control system for monitoring the electrical energy usage of a plurality of appliance loads. The system includes an energy monitor unit for each appliance load which plugs into a standard AC wall outlet and monitors power consumption and also has a power line transmitter/receiver for communicating with a master control station. The master control station receives energy usage data from each of the monitor units and stores the data for display in various user-selectable formats.
WIPO Publication No. WO0221664, which is incorporated herein by reference in its entirety, discloses a method and a system for the transmission/reception or communication of data and/or information on electric line between two electronic control devices, including: an electric, in particular a household appliance, having a first electronic control system and at least a first electric load; a monitoring or control device, having a second electronic control system, said device being located on said line between an electric power source and said first electric load. According to the invention, the transmission/reception or communication of data and/or information on said line is realized by means of an electric power modulation between said user and said device, and/or vice-versa.